Christionydd
Denbighshire

In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales
described Christionydd like this:

CHRISTIONYDD-COED and CHRISTIONYDD-KENRICK, two townships in Ruabon parish, Denbigh; near the Chester and Oswestry railway, 2 miles NNW of Chirk. Real property, of C.C., £1, 112, -of which £500 are in mines; of C-K., £27, 774, -of which £21, 360 are in ironworks, £300 in railways, and £109 in quarries. Pop., 562 and 2, 992. Iron and coal are worked.

The location is roughly halfway between Newbridge, which was in Christionydd Coed, and Cefn Mawr, which was in Christionydd Kenrick. The name "Christionydd" has not been found on a topographic map, despite a check of early large scale maps on the old-maps.co.uk site, and no authoritative statement about the location of Christionydd has been found, but for example: "The top of Newbridge was in Coed Chritionydd. Cefn Mawr was in Christionydd Kenrick." (http://www.ruabon.com/newbridge.html, accessed 14 Nov 2011).
Additional information about this locality is available for
Rhiwabon